\begin{table}
  \centering
  \caption{Absolute fractional differences between different constants as tabulated in the sources listed below. Entries marked with zero indicate that this is the value adopted by \ccl. \label{tab:constants}}
  \begin{tabular}{lccccccccc}
    \hline\hline
    & $G_{Newt}$ & $k_b$ & $\sigma_{SB}$ & $h$ & $c$ & eV & $\rho_c$ & $M_\odot$ & pc \\
    \hline
    PDG 2013 & 3e-05 & 2.1e-07 & 1.1e-06 & 7e-08 & 0.0e+00 & 3.5e-08 & 8.8e-10 & 2.2e-05 & 0.0e+00 \\[3pt]
    NIST & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & \--- & \--- & \--- \\[3pt]
    GSL 2.4 & 1.6e-04 & 1.1e-06 & 5.8e-06 & 6e-09 & 1.5e-06 & 2.1e-06 & \--- & 2.2e-04 & 7.8e-07 \\[3pt]
    CLASS & 3.0e-05 & 1.4e-06 & \--- & 1.6e-07 & 0.0e+00 & 8.4e-08 & \--- & \--- & 1.2e-09 \\[3pt]
    CODATA 2014 & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & 0.0e+00 & \--- & \--- & \--- \\[3pt]
    IAU 2015 & 0.0e+00 & \--- & \--- & \--- & \--- & \--- & \--- & 0.0e+00 & \--- \\
    \hline\hline
  \end{tabular}
\end{table}

